1. Field of the Invention
The present invention relates to an energy supply system for supplying energy in an optimal condition to energy consumers for consumption of heat and electricity in heating water, cooking, lighting, cooling and heating spaces, and operating apparatus and equipment for various other purposes.
2. Description of the Prior Art
In supplying heat and electricity as noted above, heat is produced mainly by burning a gas while electricity is transmitted from power plants. With the diffusion of air-conditioners, the demand for commercial electricity reaches its maximum during the hours from 11:00 to 17:00 in summer. Electric power companies must install power generating equipment and transmitting equipment to meet the peak power demand during such a short time in such a brief period of the year.
However, difficulties have been encountered in building new power plants in that local communities tend to oppose thermal power plants mainly on the grounds of the problem of pollution, and nuclear power plants mainly from the safety point of view. Power use patterns fluctuate throughout the year, with the consumption maximizing during a limited period of time in summer. Even if new power plants are built, the annual availability factor is very low. Consequently, it is uneconomical since new power plants will have an extremely low use efficiency for the plant investment required.
On the other hand, the demand for town gas reaches its maximum in winter and its minimum in summer. Town gas companies must install production equipment and supply equipment to meet the maximum demand in winter. Such equipment suffers a very low availability factor through the year, particularly in summer.
Thus, there is a need for development of an energy supply system, which will allow power companies and town gas companies to make effective use of their respective facilities.
Systems for supplying energy to such energy consumers who consume heat and electricity include what is known as a cogeneration system. The cogeneration system supplies commercial electric power (the power supplied from power suppliers for payment), the power obtained by driving a generator with a gas engine or gas turbine, and the waste heat from these machines.
The above cogeneration system has a high energy use efficiency to provide the advantages of low energy cost, reduced contract demand and leveled quantity of electricity. However, only an operation to minimize fuel consumption or a rated operation has been kept in view in driving the generator with the gas engines or gas turbines. The system has not been run, taking efficiency of the entire system into account, or from a national point of view.